diadophis

Definitions

from The Century Dictionary and Cyclopedia

n. A genus of Colubridæ, having the head distinct, the body slender with smooth scales, the postabdominal scutella bifid, the subcaudals all divided, the cephalic plates normal, with a well-developed loral, 2 postorbitals, 2 anteorbitals, and 2 nasals, between which latter is the nostril.